Sub-expressions

Any unrecognized identifier in an expression is assumed to be a sub-expression. An identifier is a sequence of characters that begins by an alphabetic character or an underscore, and is followed by either a numeric or several alphabetic characters.

Sub-expressions can be set to either a number, a constant value, or to a complex expression.

For more information about sub-expressions, see the Building complex expressions section in Chapter 26: Building expressions.